March Comes in Like a Lion, Volume 1 by Chica Umino

Rei Kiriyama is a child prodigy. Rei Kiriyama is also an orphan who lives alone in an empty apartment. Rei Kiriyama is a teen working in an adult's world. Life is complicated for Rei. He's an up-and-coming shogi (Japanese chess) player on the verge of turning pro but he has no homelife or much of a life period outside his board game but thankfully with the help of some life-long friends he has an opportunity start all over again.